[Ti] Screen latch problem?

[Murray E.Milligan]

I've noticed on a regular basis now when I latch my TiBook 667 and 
place it down to sleep, when I retrieve it later, it seems the screen 
is open and I've burned off substanial battery reserves. Has anyone 
else had probs with the screen latch. My extended warranty expires in a 
few months, so I'd like to get this repaired if it's a warranty issue.

Thanks for infor in advance.

Murray